package com.itheima.Filter;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import java.io.IOException;

//@WebFilter("/*")
public class DemoFilter implements Filter {

    //初始化方法,只调用一次
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("init 初始化方法执行了");
    }

    //拦截请求，可调用多次
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        System.out.println("拦截到了请求……");
        System.out.println("执行放行前的逻辑");

        //放行
        filterChain.doFilter(servletRequest, servletResponse);

        System.out.println("执行放行后的逻辑");
    }

    //销毁方法，只调用一次
    @Override
    public void destroy() {
        System.out.println("destroy 销毁方法执行了");
    }
}
